What you should know about food poisoning

And the things you think you know could be wrong

Every year millions of Americans get food poisoning. Why isn't that a major news story? Because for the vast majority, the “illness” only amounts to a slight discomfort. Often we aren't even aware we've eaten something that wasn't quite right.

Some cases of food poisoning – also known as foodborne illness – can be very serious, even deadly. In 2007 contaminated peanuts got into the food supply, resulting in a number of hospitalizations. While no deaths were officially linked to the salmonella poisoning, there were dozens of claims that tainted food caused or contributed to deaths of family members.

Besides salmonella, listeria is another common bacteria in the environment but it rarely causes infections in people. According to the U.S. Centers for Disease Control and Prevention, about 1,600 people in the U.S. get sick from listeria each year. However, in 2011 cantaloupes contaminated with listeria caused one of the deadliest foodborne outbreaks in the U.S. As recently as August a produce company recalled 5,400 cantaloupes because they might have been tainted with listeria.

Who's at risk

The people at most risk of suffering severe effects of food poisoning are the very young and very old, as well as pregnant women. That's because they often have weaker immune systems and when they eat contaminated food, they have a greater chance of becoming severely sick with problems like miscarriage or kidney failure.

One way to avoid food poisoning is to be armed with information about it. Unfortunately, says Christine Bruhn, Director of the Center for Consumer Research at University of California-Davis, there's a lot of misinformation on the subject.

Bruhn has outlined what she says are four myths about food poisoning, starting with the belief that contaminated food will taste bad. Not true, she says. Foods that are contaminated with lysteria, E. coli, salmonella, etc., can all taste great.

Another widespread belief is that once food has been cooked, it's okay to leave it sitting out, unrefrigerated, for lengthy periods of time. False again.

Put it in the fridge

If you've cooked something and have leftovers, you've got two hours to get those leftovers in the refrigerator and get them cold in order to prevent the spread of bacteria, Bruhn says. Thin-walled metal, glass or plastic containers that are shallow – no more than two inches deep -- are ideal for storage. She says bags, foil and plastic wrap also work well, especially if you have a piece of food that is large or oddly shaped.

Sometimes people get sick from eating undercooked food. Heat kills bacteria but, if the food isn't heated enough, for long enough, the bacteria lives on.

Think you can tell if food is adequately cooked, just by looking at it? Chances are, you can't. That's why Bruhn says you need to use a food thermometer.

She cites recent research from Kansas State University showing that a quarter of the burgers turned brown before they reached the recommended 160 degrees Fahrenheit.

Delayed reactions

A fourth myth is that, if you eat some tainted food, you'll know right away. Not really, Bruhn says. The most common bacteria, such as staphylococcus or clostridium, make their presence known within a few minutes to a few hours, and you can feel really awful for a day or so. The more serious bugs, such as salmonella or certain strains of E. coli, will take longer for illness to appear. Sometimes it can be days. Illness from listeria can take two months before symptoms appear, and you get really sick.

Keeping things in your kitchen clean – including your hands – is one of the most effective ways to reduce your risk of food poisoning. In a study where people were videotaped in their own kitchen, Bruhn says only half of them washed their hands before starting to prepare food.

Besides your hands, Bruhn says you should clean the cooking and preparation areas, knives and cutting boards. And don't forget the refrigerator. Bacteria can even grow there if you allow food residue to build up.